Most cable TV systems in the prior art have been broadcast only where individual programs were modulated onto 6 MHz bandwidth analog RF carriers that were frequency division multiplexed. As the internet became more popular: and telephone services became deregulated and other digital services became more popular, there has arisen the notion of delivery of digital data over cable TV systems in a portion of the bandwidth unused by the analog CATV programs. This gave rise to cable modems.
Video-on-demand services have been known in hotel television systems for several years. Video-on-demand services allow a user to select a program to view and have the video and audio data of that program transmitted to her television set. Examples of such systems include: U.S. Pat. No. 6,057,832 disclosing a video on demand system with a fast play and a regular play mode; U.S. Pat. No. 6,055,560 disclosing an interactive video-on-demand system that supports functions normally only found on a VCR such as rewind, stop, fast forward etc.; U.S. Pat. No. 6,055,314 which discloses a system for secure purchase and delivery of video content programs over distribution networks and DVDs involving downloading of decryption keys from the video source when a program is ordered and paid for; U.S. Pat. No. 6,049,823 disclosing an interactive video-on-demand to deliver interactive multimedia services to a community of users through a LAN or TV over an interactive TV channel; U.S. Pat. No. 6,025,868 disclosing a pay-per-play system including a high-capacity storage medium; U.S. Pat. No. 6,020,912 disclosing a video-on-demand system having a server station and a user station with the server stations being able to transmit a requested video program in normal, fast forward, slow, rewind or pause modes; U.S. Pat. No. 5,945,987 teaching an interactive video-on-demand network system that allows users to group together trailers to review at their own speed and then order the program directly from the trailer; U.S. Pat. No. 5,935,206 teaching a server that provides access to digital video movies for viewing on demand using a bandwidth allocation scheme that compares the number of requests for a program to a threshold and then,. under some circumstances of high demand makes another copy of the video movie on another disk where the original disk does not have the bandwidth to serve the movie to all requesters; U.S. Pat. No. 5,926,205 teaching a video-on-demand system that provides access to a video program by partitioning the program into an ordered sequence of N segments and provides subscribers concurrent access to each of the N segments; U.S. Pat. No. 5,802,283 teaching a public switched telephone network for providing information from multimedia information servers to individual telephone subscribers via a central office that interfaces to the multimedia server(s) and: receives subscriber requests and including a gateway for conveying routing data and a switch for routing the multimedia data from the server to the requesting subscriber over first, second and third signal channels of an ADSL link to the subscriber.
Video-on-demand on cable TV systems to receive requests from cable subsribers for video programs or services such as high speed internet access or access to T1 or other high speed digital telephony services have not yet completed development. Such systems receive upstream requests and deliver requested video programs with associated audio and other data, as well as bidirectional delivery of internet protocol packets from LAN or WAN sources coupled to the head end bidirectional delivery of telephony data packets to and from T1 or other high speed lines of the public service telephony network. A need has arisen for a video-on-demand service over cable TV systems as well as delivery of other services such as wideband internet and T1 telephony access over cable TV systems.